Rockwell Automation 5370-CVIM2 Module - Manual (Page 256)

Chapter 7
Inspection Tools
7–18
Figure 7.18 Example: Measuring the Chord Angle
X–axis
Chord
Feature A Feature B
0
°
The following six gage operations employ “features” to identify the edges
used for a measurement: X position, Y position, linear measure, theta,
wedge angle, and chord angle.
A gage can detect several edges, of which only one or two are required for
the measurement. Thus, the edge selection functions enable you to select
particular edges, or other features related to the edges, and determine other
aspects of the search for these edges, including search direction and search
mode. These subjects are discussed in detail in this section.
When you pick either of the buttons on the tool edit panel, a Define
Feature selection panel appears, as shown in Figure 7.19 (page 7–19).
The threshold and filter settings, along with the width selection, determine
which light/dark transitions along a gage are detected as edges. The purpose
of the feature selection function is to specify which of these edges (or
midpoints between edges) are to be identified as “features,” used as the basis
for the inspection operation. Each of these features is defined by an offset.
Note that some gage operations, such as X Position , need to specify only one
feature, while other operations, such as Linear Measure , need to specify
two features. In the first case, only the button is active; in the
second case, the button and the button are both active.
In addition to specifying the appropriate offsets, the feature selection process
also specifies the edge search direction and the edge search mode.
Feature Selection
Functions